## Random permutation matrix of order n

from PyM import *


'''
The permutation matrix associated to a permutation  {0,1,...,n-1}
is constructed, starting with the zero matrix P of order n with
integer entries, with the assignments 
   P[j,p[j]] = 1 
for j = 0,1,...,n-1.
   If the permutation is chosen at random, then we get a 
random permutation matrix.
'''

# def rd_permutation_matrix(n):
#     N = list(range(n))
#     p = rd_permutation(n)
#     P = matrix(ZZ(),n,n)		
#     for j in range(n):
#         P[j,p[j]] = 1
#     return P

P = rd_permutation_matrix(5)

show(P)

# The determinant of P is 1 if the permutation p is even and -1 if it is odd.

show('det(P) :', det(P))